The invention relates to a vehicle body.
Lateral sill panels as impact protection elements in a vehicle body are known.
The crash capability of the lateral sill panels is determined by crash tests. Euro NCAP (European New Car Assessment Program) is an organization which carries out crash tests using new automobile types, thereafter evaluating the safety of the vehicles. The side-impact post test is part of the Euro NCAP crash test. The impact of the vehicle side on a tree or mast, for example, is simulated herein in that the vehicle at 29 km/h is propelled against a solid post. This crash test is a standard requirement in the U.S. The load event FMVSS214 as a post impact is defined as follows: the vehicle on a slide moves laterally in the direction of the post (rigid, from steel); the slide is decelerated and the vehicle continues to slide against the post; the impact velocity of the vehicle on the post is 32 km/h. Potential injuries to the vehicle occupant in the region of the head, the torso, and the lower body can be detected after the crash with the aid of a dummy.
The configuration of the floorpan assembly of the vehicle and of the lateral sill panels to date has been performed by way of a metal construction. The components of the sill, the transverse seat support, and the floor panel are major participants in conventional structural concepts of the floorpan assembly. There is a clear separation in terms of components and functions between the lateral sill panel and the floorpan assembly. The sill functions as a flexural support between the A-pillar and the C-pillar and in the post crash is supported by the transverse seat support and the floor panel. The absorption of energy is performed by buckling in the transverse seat support and in the floorpan assembly, and by flexing in the lateral sill panel. The crash load is distributed across an area of a wide support region. In this manner, a large region of the floorpan assembly is deformed, and the resulting flexural stress of the lateral sill panel counteracts the intrusion. On account of the comparatively low energy absorption efficiency of metallic materials, a large material quantity has to be deformed. In the case of identical weight, this manifests itself in greater intrusions of the post into the vehicle interior or, in the case of a functionally identical layout, in a higher weight of the metallic structure.
It is an object of the invention to further reduce the intrusion and to provide a comparatively light vehicle body in a cost-effective production method having diverse design possibilities.
This object is achieved according to the invention by a vehicle body having a lateral sill panel device from fiber-reinforced plastic, which as a hollow section having an external wall element is formed as an impact face, and a floorpan structure which has a transverse seat support from fiber-reinforced plastic, which in the Y direction of the vehicle extends substantially to the external wall element.
On account of the transverse seat support extending substantially to the external wall element, crash energy can be absorbed by way of the transverse seat support. The transverse seat support thus participates directly in the absorption of energy. This enables a high consistent force level from the outset (in the initial contact between the lateral sill panel device and the post). This results in a short intrusion path in the case of a predefined crash energy. The lateral sill panel device herein is not primarily stressed in a flexural manner. The lateral sill panel device in the crash is destroyed in a localized manner at the point of impact and is not bent inward like a support across the entire vehicle length. Thus, a primary absorption of energy is provided in the continuous transverse seat support, and a secondary absorption of energy is provided in the lateral sill panel device. The lateral sill panel device thus no longer functions as a bending beam. The absorption of energy is performed from the outside to the inside, by way of the destruction of the components. The intrusion is significantly reduced on account thereof. While known vehicle bodies from metal under test conditions display an intrusion of 250 to 350 mm, a vehicle body according to the invention at the same or a lower weight can display an intrusion of now only 150 to 250 mm.
The use of fiber-reinforced plastic, in particular of carbon fiber-reinforced plastic (CRP), guarantees a low weight of the impact protection element according to the invention. The advantage herein is that a CRP part which can absorb as much energy as a metal part is only approximately one half to one third of the weight. On account thereof, the vehicle becomes lighter and consumes less fuel. Moreover, an absorption of energy by axial crushing of the fiber-reinforced plastic is provided.
Moreover, the embodiment of the lateral sill panel device having the extent of the transverse seat support according to the invention can be carried out as a monocoque construction or a hollow-section construction, since the layout of the lateral sill panel device is largely independent of the crash loads. A cost-effective production method having diverse variants in terms of design is enabled on account thereof.
Further advantages are derived from the above-described arrangement according to the invention of the lateral sill panel device and of the transverse seat support in the crash load path. The lateral sill panel device can be conceived for other functions in a targeted manner. Since the crash load is conjointly absorbed by the transverse seat support by axial crushing, the lateral sill panel device can be conceived for and optionally reduced to other overall vehicle functions (noise, vibration, and harshness (NVH), door concept, etc.). For example, the installation space of the lateral sill panel device can be reduced, leading to easier ingress to the vehicle.
In one particularly preferred embodiment, the floorpan structure has a floor panel from fiber-reinforced plastic. On account thereof, the floorpan of the vehicle is provided and the absorption of energy during the crash can be further increased.
According to one embodiment, the floor panel extends substantially to an internal wall element of the lateral sill panel device. On account thereof, only the transverse seat support having the lateral sill panel device serves initially as the side crash element, and floor panels that can be designed in a variable manner can be used. Moreover, the lateral sill panel device can be joined to the floorpan in the Y direction. In another embodiment, the floor panel extends substantially to the external wall element of the lateral sill panel device. On account thereof, the transverse seat support having the lateral sill panel device and the floor panel serve as side crash elements, on account of which the absorption of energy during the crash is further increased.
According to a further embodiment, the lateral sill panel device has an upper and a lower lateral sill panel, the external wall faces of the two being disposed so as to terminate in a flush manner in order to form the external wall element. On account thereof, the lateral sill panel device can be adapted to constructive parameters in a variable manner. It is advantageous herein for the external wall faces of the upper and of the lower sill panel to be disposed so as to terminate in a flush manner in the region of the transverse seat support, or in the region of the transverse seat support and of the floor panel, respectively.
It is advantageous herein for the floor panel to be disposed between the upper lateral sill panel and the lower lateral sill panel, and/or for the transverse seat support to be disposed between the upper lateral sill panel and the lower lateral sill panel.
In one further embodiment, the transverse seat support is received in the lateral sill panel device. It is advantageous herein for the lateral sill panel device to be formed by a single lateral sill panel and to receive the transverse seat support.
According to a further embodiment, the upper lateral sill panel is formed in two parts, as a first upper lateral sill panel and a second upper lateral sill panel. This results in diverse design possibilities.
It is thereby conceivable for the transverse seat support to be arranged between the first upper lateral sill panel and the second upper lateral sill panel. A flatter arrangement can thus be provided for the transverse seat support and for the upper lateral sill panel.
According to a further embodiment, the first upper lateral sill panel and the second upper lateral sill panel are routed upward in order for a wall element of the vehicle body, in particular a vehicle pillar, to be formed. In this way, a further wall element of the vehicle body, for example a vehicle pillar, can be formed by the upper lateral sill panels without any further components being required.
The invention also includes a vehicle having a vehicle body according to the invention.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of one or more preferred embodiments when considered in conjunction with the accompanying drawings.